Means for securing crank disks or gears against end movement.



No. 725,510. PAT-ENTEID APR; 14, 1903.."

- J. THOMSON.- MEANS FOR SECURING CRANK DISKS 0R GEARS AGAINST ENDMOVEMENT.

APPLICATION FILED JUNE 16, 1902.

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110.7%;510, 'PATENTED APR. 14, 1903;.

J. THOMSON. I MEANS FOR SECURINGORANK DISKS 0R GEARS AGAINST ENDMOVEMENT.

APPLICATION FILED JUNE 16, 1902.

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NITED STATES PATENT OFFICE.

JOHN THOMSON, OF BROOKLYN, NEW YORK, ASSIGNOR TO JOHN THOMSON PRESSCOMPANY, OF NEW YORK,'N. Y., A CORPORATION OF NEW JERSEY.

MEANS FOR SECURlNG CRANK DISKS 0R GEARS AGAINST END MOVEMENT.

SPECIFICATION forming part of Letters Patent No. 725,510, dated April14, 1903.

Application filed June 16, 1902.

To all whom it may concern.-

Be it known that I, JOHN THOMSON, a citizen of the United States,residing at Brooklyn, in the county of Kings and Stateof New York, haveinvented certain new and useful Improvements in Means for Securing CrankDisks or Gears Against End Movement, of which the following is aspecification.

My invention relates to means for securing a crank disk, gear, or otherlike device upon a shaft, and its object is to improve and simplify themeans whereby such a device can be secured against end movement withrela tion to its shaft.

The invention consists in providing a simple and efiective lock whichwhile maintaining the parts in place can readily be locked or unlockedwhen desired, and in order that the invention may be understood I haveillustrated and will specificallydescribe a preferred embodiment thereofin oneof'its simplest forms.

Referring to the accompanying drawings, Figure 1 is a side elevationshowing the end of a shaft and a crank-disk mounted thereon. Fig. 2 is afront view with a portion of the crank-disk cut away. Fig. 3 is adetached. view of the end of the shaft, showing a preferred form of agroove or keyway-slot; Fig. 4 is a side elevation showing the end of a.crank-shaft and a'crank-disk, the disk being without a recess, and. Fig.5 is a transverse sectional View of the same. A

In crank-disks or gear wheels having crank-pins or similar devices usedfor actuating a mechanism, as by means of connect ing-rods or pitmen, itis usually necessary to press the crank-disk upon its shaft very tightlyin order to prevent it from creeping off endwise. This effect is due tothe overhang of the crank, which when under heavy intermittent straintends to set up a cramping action between the shaft and its bearing inthe crank-disk. A well-known instance illustrating the foregoing is thatof a crank-action platen-press for printing and embossing.

The particular objections to the practice heretofore followed-that is,pressing the crank-disk upon the shaft so tightly as to prevent it fromcreeping'are, first, the liability of subjecting the metal to excessiveand even serial No.111,960. (No model.)

one that is simple and efficient and that is sufficient to indicate tothose skilled in the art the nature of the invention.

In the'drawings the shaft 7 is shown as having a shoulder 15 and anextended reduced portion 6, on which latter the crank-disk 13 is mountedand secured in any usual manner, as by the spline 8 in the groove 9 inthe shaft and hub'of the disk. Mounted on or the lock, shown in the formof an undercut slot or recess 5, forming a wedge-shaped channel for thelockbolt orkey, and this is preferably disposed at substantially rightangles to the spline 8. Mounted in the guide is a bolt, tongue, orwedge-key 14, which is shaped to correspond to the cross-section of thechannel and is adapted to slide closely therein. Formed in the hub orface of thecrank-disk is'a recess 10, corresponding substantiallyinshape with the slot or recess 5 and preferably arranged substantially ona line between the center of theshaft and the crank-pin.

' In assembling the parts the lock or holt14 is forced toward the innerend of the slot or recess 5, as indicated by dotted lines A B, Fig. l,and the disk is'applied to the shaft in the usual way, and then the lockor bolt 14 is forced outwardly to the position shown in full lines inFig.,1, so that the outer end of the lock or bolt enters the recess 10.In this way the lock, belt, or key not only secures the disk againstwithdrawal, buttends to prevent any endwise movement or creeping of thedisk and to aid in overcoming the intermittent strains upon the crank.

It is to be noted that it is not necessary to form a recess in thecrank-disk, as the lock or bolt can bear upon the face of the disk, as

, formed in the end of the shaft is a guide for shown in Figs. 4 and 5;but when it is desired that the face of the shaft shall be approximatelyflush with the face of the disk the recess is necessary.

It will be apparent that if in assembling the parts the face of thecrank'disk at the bottom of the recess stands slightly forward of thebottom of the slot or recess 5 the bolt or wedge-key may be caused todrive with any desired degree of resistance, thus acting to force thecrank-disk back to the shoulder on the shaft.

It is manifest that this construction is particularly advantageous inregular practice for the additional reasons to those already mentionedthat no special appliances are required for its operation. Moreover, itis fully exposed to the view of the operator, and he canreadilymanipulate the bolt or key by forcing it inward when it isdesired to remove the crank-disk.

While I have shown in the drawings a crank-disk, it is understood thatthis term is intended to embrace a crank, pulley, gear, or other devicewherein the advantages of the invention would be secured.

It is apparent that the bolt or key may also be utilized to cooperatewith or even take the place of the spline 8. In such instance the recess10 would preferably be undercut to correspond to the wedge-shapedchannel in the face of the shaft in that this would afford a greaterbearing-surface to resist torsional strain.

What I claim is- 1. The combination with a crank-disk, of a shaft havinga wedge shape or undercut recess formed in its face, a key or tonguemounted in and corresponding to the recess, and adapted to be drivenoutwardly after the crank-disk has been applied to the shaft to engageand retain the disk on the shaft, substantially as setforth.

2. The combination of a crank-disk, ashaft having a wedge shape orundercut recess formed in its face, a key or tongue mounted in andcorresponding to the recess and adapted to engage and retain the disk onthe shaft, substantially as set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN THOMSON.

Witnesses:

F. L. FREEMAN, II. M. GILLMAN, Jr.

